The difference between Html.Action and Html.RenderAction

Question

I've been trying to figure out the difference between RenderAction and Action. I don't know if I'm so concerned about the differences at this point, as to why I can't get RenderAction to work. From what I can tell, I'm passing in the correct parameters. The overload I'm using seems to be the same for both:

@Html.RenderAction(Action, Controller, Route)  @Html.Action("Breadcrumb", "Navigation", new {SeoUrl = Model.CarlineBucket.SEOURLName})  @Html.RenderAction("Breadcrumb", "Navigation", new {SeoUrl = Model.CarlineBucket.SEOURLName}) 

I get a compilation error when I try and use RenderAction:

CS1502: The best overloaded method match for 'System.Web.WebPages.WebPageExecutingBase.Write(System.Web.WebPages.HelperResult)' has some invalid arguments.

Any tips or hints? Should I not even be bothering with RenderAction?

Answer 1

Try:

@{Html.RenderAction("Breadcrumb", "Navigation", new {SeoUrl = Model.CarlineBucket.SEOURLName});} 

@Html.RenderAction() generates a write call to output something on the page and in your case you are not doing so because RenderAction renders the result directly to the Response.

Instead of

@Html.RenderAction() 

Use

@{Html.RenderAction();} 

Answer 2

From Phil Haack:

The difference between the two is that Html.RenderAction will render the result directly to the Response (which is more efficient if the action returns a large amount of HTML) whereas Html.Action returns a string with the result.